288 NATURE STUDY. 



In connection with this work, mainly indoors, some 

 field study, during the spring or fall months, of the 

 work of streams and waves in breaking down, carry- 

 ing away, and depositing rocks and soil, and in form- 

 rig gullies, valleys, hills, and other land forms, will be 

 v jry helpful as a preparation for geography. 



Air and water are earth materials as well as earth 

 >rces. The study of other earth materials may be- 

 gin during the second or third school-year, with those 

 nearest the children, limestone, sandstone, granite, soil, 

 depending largely on local conditions. All of these 

 should be approached from the life side. 



Fossil-bearing or fossiliferous limestone is particularly 

 good for beginning mineral study. It is a history as 

 well as a structure, a wonderfully interesting story 

 which any child can read when properly directed. 



Sandstone or any other stratified rock, and granite or 

 any other crystalline rock, are stories written in stone. 



The investigation of the formation and kinds of soil, 

 approached in spring through the decaying leaves or 

 the work of frost, is another gateway to the mineral 

 world. 



From such a study of earth forces, or of the agencies 

 which have changed and are changing and shaping the 

 earth, and of the materials on which these forces act, 

 the children can get the best preparation for a compre- 

 hension of the forms of land and water. Then valleys 

 and hills and bays and points and islands will have a 

 significance which mere book-work or map-study or 

 pictures or sand-table models can never give. 



